2015 INFINITI Q40

The 2015 INFINITI Q40 was a short-lived model, essentially a rebadged version of the G37 sedan. It offered a blend of luxury and performance at a competitive price point. Owners generally appreciate the Q40’s powerful V6 engine, comfortable ride, and stylish design. However, some common complaints include a dated interior design, less fuel-efficient than some competitors, and some reliability concerns that plague the G37. All 2015 Q40 models came equipped with a 3.7-liter V6 engine producing 328 horsepower and 269 lb-ft of torque, paired with a 7-speed automatic transmission.

Engine

3.7L V6 (VQ37VHR)

• Timing Chain Rattle
  • Description/Symptoms: A rattling noise, especially on cold starts, originating from the front of the engine. This is often due to wear on the timing chain tensioners or guides. The noise may diminish as the engine warms up. In severe cases, it can lead to engine performance issues.
  • Solution: Replacement of the timing chain, tensioners, and guides.
  • Estimated Cost to Fix: $1,500 - $3,000+
  • Recalls: None Found
• Oil Consumption
  • Description/Symptoms: Some owners have reported excessive oil consumption, requiring frequent top-ups. This can be due to worn piston rings or valve stem seals. Blue smoke may be visible from the exhaust.
  • Solution: In minor cases, switching to a higher viscosity oil may help. In severe cases, engine repair or replacement of piston rings/valve stem seals is necessary.
  • Estimated Cost to Fix: $800 - $5,000+ (depending on severity and repair method)
  • Recalls: None Found
• Valve Cover Gasket Leaks
  • Description/Symptoms: Oil leaks from the valve cover gaskets, often onto the exhaust manifolds, leading to a burning smell.
  • Solution: Replacement of the valve cover gaskets.
  • Estimated Cost to Fix: $200 - $500
  • Recalls: None Found

Transmission

7-Speed Automatic (RE7R01A)

• Rough Shifting
  • Description/Symptoms: Harsh or jerky shifting, especially between certain gears. This can be caused by low transmission fluid, worn solenoids, or issues with the valve body.
  • Solution: Check and potentially flush/replace transmission fluid. If the problem persists, solenoid or valve body replacement may be necessary.
  • Estimated Cost to Fix: $150 (fluid change) - $1,500+ (solenoid/valve body replacement)
  • Recalls: None Found
• Transmission Slipping
  • Description/Symptoms: The transmission hesitates or fails to engage when accelerating. This can be caused by internal wear of the clutch packs or other components.
  • Solution: In most cases, a transmission rebuild or replacement is required.
  • Estimated Cost to Fix: $3,000 - $6,000+
  • Recalls: None Found

Suspension

• Front Lower Control Arm Bushing Failure
  • Description/Symptoms: Clunking or rattling noises from the front suspension, especially when going over bumps. This is caused by worn or cracked bushings on the lower control arms.
  • Solution: Replacement of the lower control arms, including new bushings.
  • Estimated Cost to Fix: $300 - $800 per side
  • Recalls: None Found
• Strut Mount Noise
  • Description/Symptoms: Squeaking or creaking sounds when turning the steering wheel or going over bumps, indicating wear or damage to the strut mounts.
  • Solution: Replacement of the strut mounts.
  • Estimated Cost to Fix: $200 - $600 per strut
  • Recalls: None Found

Electrical

• Navigation System Issues
  • Description/Symptoms: Malfunctioning navigation screen, inaccurate GPS location, or system freezes.
  • Solution: Software update, replacement of the navigation unit.
  • Estimated Cost to Fix: $100 (update) - $1,000+ (replacement)
  • Recalls: None Found
• Bluetooth Connectivity Problems
  • Description/Symptoms: Difficulty pairing devices, intermittent connection drops, or poor audio quality during calls.
  • Solution: Software update, replacement of the Bluetooth module.
  • Estimated Cost to Fix: $0 (update) - $300+ (replacement)
  • Recalls: None Found

Exterior

• Headlight Condensation
  • Description/Symptoms: Moisture buildup inside the headlight housings.
  • Solution: Replacement of the headlight assemblies, resealing the headlight assembly.
  • Estimated Cost to Fix: $300 - $1,000+ (per headlight, depending on repair or replacement)
  • Recalls: None Found

Interior

• Sunroof Issues
  • Description/Symptoms: Sunroof not opening or closing properly, getting stuck, or making unusual noises.
  • Solution: Lubrication of the sunroof tracks, repair or replacement of the sunroof motor or components.
  • Estimated Cost to Fix: $50 - $800+
  • Recalls: None Found
• Door Lock Actuator Failure
  • Description/Symptoms: Door locks failing to lock or unlock remotely or manually.
  • Solution: Replacement of the door lock actuator.
  • Estimated Cost to Fix: $150 - $400 per door
  • Recalls: None Found

Summary

The 2015 INFINITI Q40, while offering a strong engine and comfortable ride, is not without its potential issues. Engine-related problems, such as timing chain rattle and oil consumption, can be costly to repair. Transmission issues, like rough shifting or slipping, are also a concern. Suspension issues like lower control arm bushings are also common. Electrical glitches and interior component failures can further add to the ownership costs. Overall, the severity of potential issues ranges from minor inconveniences to significant repairs. Potential buyers should have a pre-purchase inspection performed by a qualified mechanic to assess the condition of the engine, transmission, and suspension.